Cost-effectiveness of silvicultural measures to increase substrate availability for wood-dwelling species: A comparison among boreal tree species
Abstract:This study analysed the cost-effectiveness of silvicultural measures that increase substrate availability for saproxylic (wood-dwelling) species. Mixed stands of Norway spruce (Picea abies L.), Scots pine (Pinus sylvestris L.) and birch (Betula pubescens Ehrh and Betula pendula Roth) or aspen (Populus tremula L.) in three regions of Sweden were modelled. Inverted cost-effectiveness was calculated by dividing the economic cost associated with a silvicultural measure by the increase in coarse woody debris (CWD) and an index reflecting substrate availability for red-listed saproxylic beetles and cryptogams, compared with a reference scenario maximizing economic profit. Tree species had a large impact on the cost-effectiveness of green tree retention: Scots pine was the most costly tree species to retain and aspen and birch the most cost-effective. Tree species also had an impact, albeit smaller, on the cost-effectiveness of the creation of high stumps. It was most cost-effective to create high stumps from birch and aspen in southern Sweden, whereas in northern Sweden it was more cost-effective to create high stumps from pine and spruce. Therefore, when increasing the amount of coarse woody debris (CWD), deciduous trees should be targeted in southern Sweden more than in the north. However, it is important that CWD is created from all tree species, because different tree species support different assemblages of saproxylic species. As regards measures that are not associated with particular tree species, retention of snags at final harvest is a cost-effective measure in all regions, whereas increasing the rotation period is costly.
Document Type: Research Article
Publication date: February 1, 2010